Looking to install a single point push button release sling or quality equivalent (no polymer attaching clip on sling) .

A good quality magazine vice block. The only one I've been able to locate so far on the internet has a less than good reviews (i.e.; fits loosely in mag well).

Also, I'd like to get a new castle nut. I sort of mashed mine up installing a single point sling mount that I'm not happy with.

TIA

For sling, check these guys out:
Sear Tactical Innovations

For vise block, consider the vise block from Brownells:
AR-STYLE .308 LOWER RECEIVER VISE BLOCK | Brownells

For receiver extension nut, consider DPMS:
AR-15/M16 M4 RECEIVER EXTENSION CASTLE NUT | Brownells

You might consider this Troy part for the single point push button release:

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Another source for heavy duty slings:
Special Operations Technologies

Thanks Gentlemen. I appreciate your feedback

Just order one of those!!! I'll post picks on how it turns out.

I had to modify mine to get the troy sling mount to work. Just a little dremel work on the tabs that hang over the lower receiver.